Wafer thinning technology is important to package development. Current wafer thinning methods include the in-line wafer B/G (Back Grinding) system and the DBG (Dicing Before Grinding) process. The inline wafer B/G systems have used the film adhesive process whereby the wafer is thinned by backgrinding and then is diced. However, a conventional DBG process did not use the film adhesive process because the separated die created by the DBG process had a tilt after B/G tape removing.
A conventional dice before grinding process is shown in FIGS. 1-7. FIG. 1 illustrates a wafer 10 having a first or front side 12 being grooved using a grinding wheel 14 or other grooving technique. FIG. 2 illustrates adhering a back grinding tape 16 to side 12 using a roller 18. The structure of FIG. 2 is then inverted exposing the second or back side 20 of wafer 10 at a material removal station 21 permitting a grinding wheel 22 to grind second side 20. Grinding wheel 22 removes sufficient material to expose the grooves 23 formed by grinding wheel 14 thus creating a diced wafer 25. FIG. 4 illustrates the application of dicing tape 24 to second side 20 using a roller 26. The structure of FIG. 4 is then inverted to permit back grinding tape 16 to be remove as illustrated in FIG. 5. FIG. 6 illustrates the structure of FIG. 5 with the back grinding tape completely removed to expose the diced wafer 25. FIG. 7 is an enlarged view of a number of the diced die 28 of FIG. 6. FIG. 7 illustrates what is termed die tilt. Die tilt is created because the adhesive strength of dicing tape 26 is not sufficient to prevent the shifting of die 28 during the removal of back grinding tape 16. This die tilt is a problem because it makes picking and placing die 28 more difficult thus increasing the complexity and cost of subsequent chipmaking operations.